Waterproof connectors are conventionally used, for example, for electrical connections in automobiles. The waterproof connector sealing member shown in FIGS. 12A and 12B (see Japanese Utility Model Application Kokai No. H2-119372), for example, has been used for a waterproof connector.
In the waterproof connector sealing member 101, shown in FIG. 12B, a plurality of electrical wire insertion holes 103 extend between two main surfaces of a substantially circular flat, plate-shaped sealing main body 102. A plurality of ring-shaped sealing projections 104 are provided on the inner wall surface of each of the electrical wire insertion holes 103, and the sealing projections 104 of respectively adjacent electrical wire insertion holes 103 are formed in different positions with respect to each other along the axial direction of the electrical wire insertion holes 103.
The waterproof connector sealing member 101 is attached to a sealing member receiving cavity of a waterproof connector housing (not shown in the figures), and as a result of the outer circumferential surface of the sealing main body 102 contacting and pressing against the inner circumferential surface of the sealing member receiving cavity, a seal is formed between the outer circumferential surface of the sealing main body 102 and the inner circumferential surface of the sealing member receiving cavity.
Furthermore, a plurality of contacts (not shown in the figures) to which electrical wires (not shown in the figures) are connected are inserted into the electrical wire insertion holes 103 from the side of the contact insertion surface (right side in FIG. 12B) of the waterproof connector sealing member 101, with the side of the contacts inserted first, and when the insertion of these contacts is completed, the contacts are supported by being positioned inside contact receiving cavities (not shown in the figures) in the housing that is located on the inside (left side in FIG. 12B) of the waterproof connector sealing member 101. Moreover, the electrical wires that are connected to the contacts are positioned inside the electrical wire insertion holes 103 in the waterproof connector sealing member 101. Furthermore, the sealing projections 104 press the electrical wires from the peripheries of the electrical wires; as a result, the electrical wires are sealed, and the contacts inside the contact receiving cavities are waterproofed from the outside by the sealing projections 104.
In the insertion of these contacts into the electrical wire insertion holes 103, since the sealing projections 104 of respectively adjacent electrical wire insertion holes 103 are provided in different positions with respect to each other along the axial direction of the electrical wire insertion holes 103, the pressing force by means of the sealing projections 104 is not concentrated in specific locations along the axial direction between the respectively adjacent electrical wire insertion holes 103, so that the insertion of the contacts can be accomplished relatively easily.
Furthermore, the waterproof connector sealing member shown in FIGS. 13A and 13B (see Japanese Patent Application Kokai No. S62-241277) has also been used in the past in a waterproof connector.
As is shown in FIGS. 13A and 13B, in this waterproof connector sealing member 201, a plurality of electrical wire insertion holes 203 that extend between the two main surfaces of a substantially rectangular flat plate-shaped sealing main body 202 are formed in this sealing main body 202. A plurality of projecting ribs 204 are provided around the sealing main body 202, and receiving holes 205 are formed in the peripheries of the respective electrical wire insertion holes 203 on the side of the back surface of the sealing main body 202 as shown in FIG. 13B.
This waterproof connector sealing member 201 is attached to a sealing member receiving cavity 211 in a plug housing 210. In this case, a seal is created between the outer circumferential surface of the sealing main body 202 and the inner circumferential surface of the sealing member receiving cavity 211 by the outer circumferential surface of the sealing main body 202 contacting and pressing against the inner circumferential surface of the sealing member receiving cavity 211. In this case, positioning projections 213 provided on the plug housing 210 are inserted into the receiving holes 205 formed in the sealing member 201, so that the electrical wire insertion holes 203 in the sealing member 201 are positioned in locations corresponding to contact receiving cavities 212 in the plug housing 210.
Then, a plurality of contacts 220 to which electrical wires 230 are connected are inserted into the electrical wire insertion holes 203 from the side of the contact insertion surface (left side in FIG. 13A) of the waterproof connector sealing member 201, with the side of the contacts 220 inserted first, and when the insertion of these contacts is completed, the contacts 220 are supported by being positioned inside the contact receiving cavities 212 in the plug housing 210. Furthermore, the electrical wires 230 connected to the contacts 220 are positioned inside the electrical wire insertion holes 203 in the waterproof connector sealing member 201, so that the electrical wires 230 are sealed, and the contacts inside the contact receiving cavities 212 are waterproofed from the outside. Furthermore, the contacts 220 in the plug housing 210 mate with male type contacts 242 that protrude to the interior of a mating recessed part 241 of a mating connector 240, so that these parts are connected to each other.
However, the following problems have been encountered in these conventional waterproof connector sealing members shown in FIGS. 12A and 12B, and 13A and 13B:
Specifically, in the case of the waterproof connector sealing member 101 shown in FIGS. 12A and 12B, there is no relief area for the compressed sealing member around the electrical wire insertion holes 103 (especially on the outside of the electrical wire insertion holes 103) as shown in FIG. 12A. When the electrical wires are positioned inside the electrical wire insertion holes 103 by inserting the contacts into the electrical wire insertion holes 103, the sealing projections 104 and the sealing material around the sealing projections 104 are compressed by the electrical wires in the direction of expansion to the outside. However, since there is no relief area for the compressed sealing member around the electrical wire insertion holes 103 (especially on the outside of the electrical wire insertion holes 103), if a thick wire is inserted into a specified electrical wire insertion hole 103, for example, the sealing material escapes into the electrical wire insertion holes 103 adjacent to this electrical wire insertion hole 103, so that these electrical wire insertion holes 103 are longitudinally deformed to a great extent. In such a case, if thin electrical wires are inserted into these greatly deformed electrical wire insertion holes 103, there is a danger that a gap will be created between the electrical wires and the sealing projections 104, so that the desired sealing characteristics will not be obtained.
Furthermore, in the case of the waterproof connector sealing member 201 shown in FIGS. 13A and 13B, although the receiving holes 205 into which the positioning projections 213 of the plug housing 210 are inserted are formed around the electrical wire insertion holes 203, the receiving holes 205 are not formed around all of the electrical wire insertion holes 203 as shown in FIG. 13B. Regions where no receiving hole 205 is formed are present especially in the vicinity of the outer edges. Accordingly, there is a risk that the electrical wire insertion holes 203 in the vicinity of the regions where no receiving hole 205 is formed will be positionally shifted with respect to the contact receiving cavities 212. If a thick electrical wire is inserted into one of these positionally shifted electrical wire insertion holes 203, the sealing material escapes into the electrical wire insertion holes 203 that are adjacent to this electrical wire insertion hole 203, so that these electrical wire insertion holes 203 are longitudinally deformed to a great extent. In such a case, if thin electrical wires are inserted into these greatly deformed electrical wire insertion holes 203, there is a danger that a gap will be created between the electrical wires and the sealing projections inside the electrical wire insertion holes, so that the desired sealing characteristics will not be obtained.